Two-dimensional dynamics of solid fiber Z-pinches: Hot spots, photon emission, and other diagnostics from a computational viewpoint

Abstract

Summary form only given. It has been demonstrated that interesting, long-lived fusion plasmas can be created by discharging modern high-voltage pulsed power generators through frozen deuterium fibers or solid fibers of other materials. One- and two-dimensional magnetohydrodynamic computations of the formation and evolution of fiber-formed plasmas have been performed. The computations use cold-start initial conditions in all attempt to compute the behavior of the pinches from t =0. The one-dimensional computations show that, prior to complete fiber ablation, current is carried by low-density, hot plasma which has been ablated from the fiber; the computations predict that the fiber persisted longer than expected in early experiments. The two-dimensional computations predict m =0 behavior of the fiber-formed pinches. The m =0 behavior begins in the hot, exterior plasma prior to complete ablation of the fiber and enhances the fiber ablation rate. It is found that diagnostics based on the computed two-dimensional density/temperature profiles agree qualitatively and quantitatively with experimental observations